British Insects: the Families of Diptera


L. Watson and M. J. Dallwitz


Adult insects. Very small to small (about 3–4 mm long); not stilt-legged. Antennae 10–14 segmented (ostensibly of two, terminated by a multi-segmented style-like appendage); ‘simple’ to ‘modified’ (the first and second segments stout, the remainder longer and more slender); not aristate. Ocelli absent. Eyes asymmetric, nearly or quite connected above the antennae (in both sexes). The maxillary palps 3–5 segmented (longer than the antennae); drooping. Thorax without a continuous dorsal suture (i.e., without the V-shaped suture of Tipulidae). Wing veins reaching the margin 6–8. Wings without a discal cell; without a sub-apical cell; without a closed anal cell. The costa extending around the entire wing. Sub-costa apparent; terminating blind (short). Wings with the lower calypter much reduced or absent.

Larvae and pupae. The larvae aquatic (generally in thin trickles of water over rocks and stones); eucephalic. The pupae without a puparium.

Comments. Sluggish, small, bare, drab brown or yellowish, small-headed flies.

Classification. Suborder Nematocera; Division Culicomorpha; Superfamily Chironomoidea.

British representation. 3 species in Britain. Genera 1; Thaumalea.

Illustrations. • Thaumalea testacea (from Walker).

To view the illustrations with detailed captions, go to the interactive key. This also offers full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. British insects: the families of Diptera. Version: 1st January 2012.’.